Evaluate the safety of the cp and ts RS virus vaccine strains in RS virus seropositive adults, the safety of candidate cp and ts vaccine strains in RS virus seropositive children, and the safety, infectivity, immunogenicity, genetic stability, transmissibility and ability of the candidate RS virus vaccines to induce protective immunity in RS virus seronegative infants and children. During the report period, 2 vaccines were evaluated in 15 seropositive children and 16 seronegative children. No adverse events have occurred. Enrollment is ongoing.